Tuning Topologies
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Tuning a Random Access Indexing Topology

Indexing is primarily IO driven. Tuning indexing tends to focus on the search index (Solr or Elasticsearch). Problems with indexing running too slow will often manifest as Kafka not commiting in time. This results from the indexing backing up so that it fails batches and the poll interval in Kafka is exceeded. The issue is actually with the index rather than Kafka.